Carburetor



Oct. 22, 1929. A. P. PLAUT 1,732,531

GARBURE'I'OR Original Fil ed March 8, 1919 Patented st. 22, 1929 UNITED STATES PATENT? OFFIQE ANTUINE 'IPROSPER PLA'UT, 0F FLINT, MICHIGAN, ASSIGNOR OF ONE-HALF TO THE RUEFETS TlOlll' OF MICHIGAN BRASS MANUFACTURING COMPANY, OF DETRUIT, MICHIGAN, A. CORPORA- UMRHURETUF.

application flied March a, 1919, serial No. ttttto. Renewed septemter G, that.

This invention relates to certain new and useful improvements in carburetors, and is an improvement on the construction shown in my Patent No. 1,555,604, dated September 29, 1925, the object being to provide means for carrying fuel quickly above the throttle when the suction through the throat of the Venturi is insumcient and the capacity of the idling by-pass is inadequate for the purpose.

Another object of my invention is to pro vide a carburetor having primary charge forming means and a compound by-pass whereby the proper mixture will be formed at all speeds-of the engine to which the carburetor is attached, one of the by-passes supplying the mixture at very slow speed and the other mixture when the engine is idling.

Uther and further objects and advantages of the invention will be hereinafter set forth and the novel features defined by the appended claims.

lln the drawing:

Figure l is a vertical section through my improved carburetor.

Figure 2 is a section taken on line 22 of Figure 1, showing the air chamber, and

Figure 3 is an enlarged section on line 3-3 of Figure 1.

Like numerals of'reference refer to like parts in the several figures of the drawings.

In carryin out one form of my invention ll employ a tu ular body 1 which is preferably formed of a casting having an air passage 2 provided with an enlargement at its lower end, in which is secured the angled end of a lateral air inlet pipe 3 provided with the usual choke valve 4.

The upper end of the air passage 2 terminates in a throttle chamber 5 in which is mounted a throttle valve 6 of the ordinary formed in the air tube.

of jets, through which the partially atomized fuel is delivered into the Venturi tube.

The annular emulsifying chamber 8 cornmunicates with an accelerating chamber formed in the body 1 through a bore or passage 11, which together with the annular emulsifying chamber 8 and passages 9 form an emulsion passage. This chamber 10 is formed with an enlarged lower end in which is arranged a plug provided with a threaded bore adapted to receive a threaded fuel nozzle 12. The fuel nozzle 12 is provided with a calibrated opening for delivering all of the fuel required by the carburetor. A plug 1d closes the threaded opening l3 through which the nozzle is inserted.

The accelerating chamber 10 is provided with a series of air inlet ducts 15 extending from an air chamber 16 formed in the body parallel with the accelerating chamber. The air chamber 16 is provided with an air inlet tube 17 at its upper end, in which is screwed a tubular valve 18, the lower end of the valve being adapted to seat on a. valve seat 19 The wall of the air tube is provided with openings 20 for admitting additional air when desired, and it will be seen by this construction that by having the tubular valve with a calibrated air passage, a predetermined quantity of air will be admitted to the air chamber at all times, and by the particular construction of valve and air inlet, an additional suppl of air can be admitted into the air cham er by adjusting the valve.

The body 1 has formed integral therewith a fuel reservoir 21 provided with a fuel outlot 21'- extending downwardly, so that the fuel from the reservoirvwill pass through the nozzle and be delivered into the accelerating chamber. The fuel reservoir 21 is provided with the usual inlet, and float, not shown, for maintaining fuel in the reservoir at a level on line AA, which is ap roximately mid way of the annular emulsifying chamber.

The wall of the-air passage 2 is enlarged as shown at 22 and is provided with a vertical bore 23 in vertical alignment with the chamber 10 in the lower end of which is arranged an idling tube 24 ofiset as shown at .24, which extends down into the chamber and terminates below the nozzle 12, where it has a small orifice 24 calibrated to admit a smal amount of fuel suitable for idling. The upper end of the bore 23 communicates with a diagonally upwardly extending bore 25 extending into the throttle chamber 5 slightly above the closed position of the throttle valve6 therein. A lateral tubular projection 26 is formed on the enlarged portion 22 having a bore 27 forming an air paspassageway for intercepting emulsion in the passage 11 and transferring the same above the throttle for slow speeds. The tube 33 is inserted through'the bore 32 from the outside of the carburetor body and the u per end of the bore is afterwards closed by t e plug 33'.

The operation-of the carburetor is as follows:

When the engine is not in operation the fuel stands at the level designated by the line AA slightly submerging the lower end of the transfer tube 33. Under idling conditions with the throttle only slightly open, as shown in full lines, in Figure 1, fuel is delivered to the mixing chamber above the throttle by means of the idling tube 24, this causing a slight lowerin of the fuel level in the accelerating cham r 10 and passa e -11, so that the bottom of the transfer tu 33 is no longer submerged in the liquid. Un-

der these conditions substantiall' all of the fuel is supplied through the tu 24'whi1e air or occasionally emulsion may be drawn through the transfer tube 33. Z

Upon opening-the throttle further, more fuel is drawn from the fuel nozzle 12 and air from the air ducts 15 accordingl The emulsion so formed is drawn through emulsion passage 11 where it is intercepted and transferred above the throttle by transfer tube 33. As thistransfer tube 33 has a large capacity, it will handle all of the fuel delivered by the nozzle 12 until the emulsion going through passage 11 has reached a velocity high enough to go by the transfer tube and reach the Venturi throat. When this hap'pens,the velocity at the Venturi throat is high enough to carry-it quickly above the throttle. This stageof operation is reached at a point far beyond the capacity of an ordinary idling by-pass.

The transfer passage 33 remains in action until the depression in passage 11 is greater than the depression at the outlet of passage 25 above the throttle. This point is not reached until the motor has passed the intermediate speeds and reached high speeds.

In the above description I have illustrated one embodiment of my invention, but it is to be understood that the invention can be embodied in various modified constructions. The principal feature of the invention is the provision of the transfer tube having one end communicating above the throttle and the other end in the emulsion passage between the fuel nozzle and the throat of the Venturi.

What I claim is:

1. In a carburetor, the combination with an air conduit having a Venturi therein and a throttle above the Venturi, of an emulsifying chamber, means for introducing fuel thereinto, means for introducing air into said emulsifying chamber, a'fuel passage between said emulsifying chamber and said air conduit opening into the latter substantially at the throat of said Venturi, a by-pass connected to said air conduit above said throttle and extending into said emulsi ing chamber to a point below the normal evel of the fuel therein, and an auxiliary by-pass also communicating with said conduit above said throttle and extending into said emulsifying chamber at a point adjacent said fuel passage.

2. In a carburetor, the combination with an air conduit having a Venturi therein and a throttle above the Venturi, ofan emulsifying chamber, means for introducing fuel .thereinto, a series of vertical s aced air conduits communicating with sai emulsifying chamber, a fuel passage between said emulsifyingchamber and said Venturi connecting with the latter substantially at the throat thereof, a. by-pass connected to said air conduit above said throttle and extending into said emulsifying-chamber to a point adjacent the bottoin thereof, and an auxiliary bypass also communicating with said conduit above said throttle and extending into said emulsifying chamber at a point adjacent said fuel passage.

3. In a carburetor, the combination of an air inlet, a mixture outlet, 11 throttle at the mixture outlet end, a mixing chamber between said air inlet and mixture outlet, an

emulsion passage leading into said mixing I chamber nozzle means for su pl in substantially all of the fuel ut-ilihed g for admitting air to said emulsion passage and a transfer passageway having one end thereof connected to the mixture outlet above the throttle and the other end connectmg with said emulsion p between the -discharge end thereof on theone Hand and by said carburetor to said emulsion passage, means" Bil till

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nraaaar l the nozzle means and the air admitting meanson the other hand,

l. in a carburetor, the combination of an air inlet, a mixture outlet, a throttle at the mixture outlet end, a mixing chamber be tween said air inlet and'mixtureoutlet, an emulsion passage leading into said mixing chamber and having a portion thereof extending in a direction transverse to the vertical, nozzle means for supplying substantially all of the fuel utilized by said can buretor to said emulsion passage, means for admitting air to said emulsion passage and a transfer passageway having-one end thereof connected to the mixture outlet above the throttle and the other end connecting with said emulsion passage at the transversely extending portion thereof between the mixing chamber on the one hand and the nozzle means and the air admitting means on the other hand.

5. lln a carburetor, the combination of an air inlet, a mixture outlet, a throttle at the mixture outlet end,a mixing chamber between said air inlet and mixture outlet, a constant level fuel supply chamber, an emulsion passage leading into said mixing chamber, nozzle means for supplying from said constant level fuel supply chamber substantially all of the fuel utilized by said carburetor to said emulsion passage, means for admitting air to said emulsion passage and a transfer passageway of a sulificientsize throughout its length to accommodate fuel greatly in excess of that required for idling,

one end of said transfer passageway connecting with said mixture outlet above said throttle and the other end opening into said emulsion passage at a point located in the vicinity of the plane of the constant fuel level where by emulsion only is delivered through said transfer passageway, the said other end of said transfer passageway being between the mixing chamber on the one hand and both the air admitting means and the nozzle means on the other hand.

ti. lln a carburetor, the combination of an air inlet, a mixture outlet, a throttle at the mixture outlet end, a mixing chamber between said air inlet and mixture outlet, a constant level fuel supply chamber, an emulsion passage leading into said mixing chamber, nozzle means for supplying from said constant level fuel supply chamber substantially all of the fuel utilized by said carburetor to said emulsion passage, means for admittting air to said emulsion passage, a transfer passageway of a sufdcient size throughout its length to accommodate fuel greatly in excess of that required for idling, one end of said transfer passage way connecting with said mixture 1 outlet above said throttle and the other end opening into said emulsion passage at a point located in the vicinity of the plane of the constant fuel level whereby emulsion only is delivered .throttle and'transferring the fuel to through said transfer passageway, the said other end of said transfer passageway being between the mixing chamber on the one hand and both the air admit-ting means and the nozzle means on the other hand, and a conduit leading above the throttle and extending into passage increasing in degree as the air flow through said main air passageway increases, means for bleeding air into said emulsion passage, and means communicating with said emulslon passage at a point between the fuel delivery means and said air passageway and being adapted to intercept the fuel from said fuel delivery means prior to its discharge through said emulsion passageway below said a said air passagewayabove said throttle.

8. in a carburetor, the combination of a main air passageway, a throttle therein, a constant level fuel reservoir,'nozzle means leading from said reservoir adapted to supply substantially all the fuelrequired by the carburetor, an emulsion passage discharging into said air passageway below said throttle and leading from said nozzle means, an air inlet leading to said emulsion passage, a transfer conduit communicating with said air passageway above said throttle, said transfer conduit having an inlet end extending into said emulsion passage between said air passageway on the one hand and the air inlet and said nozzle means on the other hand, said inlet end being arranged in such position as to intercept fuel flowing in said emulsion passage and transfer the same above the throttle.

9. ln a carburetor, the combination ofa mixture passageway having a throttle there in, an air-bled emulsion passage communicatingwith said mixture passageway below said throttle, calibrated fuel nozzle means adapted to supply into said air-bled emulsion passage all of the fuel required by said carburotor, and a transfer conduit having its outlet end in said mixture passageway above said throttle and having its inlet end in said airbled emulsion passage between said nozzle means and said mixture passageway.

ltn testimony whereof l hereunto atlix my signature,

drl l'll Ull l'E Plttldlflillt P'lbhU'l. 

